Sounds similar to what Wolfram Alpha can do: http://www.wolframalpha.com/input/?i=2+slices+of+bread+%2B+1+slice+swiss+cheese+%2B+1%2F2+avocado+%2B+1+slice+toma

Sounds similar to what Wolfram Alpha can do: http://www.wolframalpha.com/input/?i=2+slices+of+bread+%2B+1+slice+swiss+cheese+%2B+1%2F2+avocado+%2B+1+slice+tomato&lk=3 http://www.wolframalpha.com/input/?i=2+slices+of+bread+%2B+1...